American officials are warning military personnel to be wary after a group claiming affiliation with the Islamic State posted the purported addresses of 100 US service members and called for attacks on them by supporters of the militant group in the US.
A group that identified itself as the Islamic State Hacking Division (ISHD) listed names and addresses that allegedly belong to Army, Navy, and Air Force personnel in order to encourage so-called "lone wolf" attacks, according to the SITE Intelligence Group, a company that tracks the online activity of militant organizations.
"With the huge amount of data we have from various different servers and databases, we have decided to leak 100 addresses so that our brothers in America can deal with you," the ISHD said a post that accompanied the addresses.
Calling on supporters to kill those listed, the group wrote, "We have made it easy for you by giving you addresses, all you need to do is take the final step, so what are you waiting for?"
A press officer at the Pentagon told VICE News that they were aware of the alleged threat but could not confirm the addresses were accurate or obtained via hacking.
"We are looking into it," a Pentagon spokeswoman wrote in an emailed statement. "The safety of our service members is always a concern."
It's unclear if the information was actually hacked from internal accounts or was simply available online or in public records. A Defense Department official told theNew York Times that that most of the information could be found easily online in public records, search engines, and social media.
Lt. Col. John Caldwell, a spokesman for the Marines, told VICE News that the Naval Criminal Investigative Service notified all affected Marine personnel in person about the threat.
"It is recommended Marines and family members check their online/social footprint, ensuring privacy settings are adjusted to limit the amount of available personal information," Caldwell said. "Vigilance and force protection considerations remain a priority for commanders and their personnel worldwide."
The hackers targeted military members who have been linked to airstrikes on the militant group in news articles and other media, according to the New York Times. However, some names listed seemingly had no affiliation with current bombing campaigns.
This not the first time a group claiming affiliation with the Islamic State has used the internet to strike out at the US military. The US Central Command (Centcom) had their Twitter and YouTube accounts hacked by Islamic State supporters earlier this year.
Centcom Chief of Staff Major General Michael Garrett warned military members to be careful about putting information online where it can be easily found.
"I ask that you maintain vigilance and continue to safeguard yourself and your family's security while interfacing on the internet and participating in social media," Garrett said in a statement posted on the Centcom Facebook page.
Several military members were also threatened online when Centcom's Twitter and YouTube accounts were hacked in January.
Before the compromised accounts were shut down, one message read, "American soldiers, we are coming, watch your back!" next to what appeared to be a list of the names and phone numbers of military personnel.
A second message warned: "We won't stop! We know everything about you, your wives, and children."
VICE News' Liz Fields contributed to this report.
Follow Gillian Mohney on Twitter: @gillianmohney